British light-heavyweight Joshua Buatsi made a winning yet underwhelming start to his career under new promoters with a decision win over Parker in Manchester.
The Olympic bronze medallist's work rate seemingly secured him a judges' verdict in a competitive 10-round bout at the Co-op Live Arena.
But the challenger landed significant shots, connecting with powerful individual punches in a contest where the approaches didn't complement each other, with excessive holding spoiling the contest.
Two judges judged it 96-94 for to Buatsi, with the final judge a 95-95 draw.
"It wasn't my finest showing but what defines champions? They succeed," Buatsi stated in the ring as he was met by disapproval from the crowd.
The British fighter got back to winning after his initial pro loss - an epic battle with his previous opponent in last winter - to secure a 20th pro success.
Various analysts felt the challenger, 31, deserved the victory but the contender suffered the second setback of his 28-match career.
The Champion Secures Win in Uneventful Match
Buatsi's progress has plateaued in recent years through management issues and long spells of inactivity.
Previously predicted as the future of the British fight scene, he now is positioned trying to achieve expectations - possibly in what appears to be a final roll of the dice - under new promotional backing.
He opened tentatively, with neither fighter ready to take risks in a cagey initial rounds.
Parker, whose single earlier setback came at super middleweight against his former opponent in 2022 after damaging his hand in the contest, was competing in only his second fight at light-heavyweight.
By the fight's midpoint, Parker had stayed in contention, making life awkward for Buatsi, who worked behind a tight guard to narrowly win the better periods.
The spectators' acceptance wore thin during regular grabbing, with Parker falling to the floor various instances during close exchanges.
Parker finished the stronger, but several stanzas were challenging to assess. However, ex-champion Carl Frampton - commentating on Dazn - had it particularly wide for Parker, giving Buatsi just a single round.
Buatsi advances, but with the caliber of heavy hitter Benavidez, and Eastern European fighter Dmitry Bivol dominating the weight class, the road to world glory - based on this performance - still looks steep.
Hatton Homage Fuels All-Manchester Contest
In the secondary fight, Arthur defeated Bradley Rea by split-decision in a terrific Manchester vs Manchester battle to secure the European light heavyweight belt.
The venue fell silent for a deeply poignant memorial ahead of the contest as 10 bells sounded in remembrance of Manchester's own Ricky Hatton, who succumbed at age 46 in last month.
It was the premier televised match card in the city since Hatton's passing. As the last bell disappeared, the stillness transitioned to a shout of "there's just one Hatton".
The competition during the bout equaled the feeling. Arthur was floored by a powerful punch flush on the chin in the early round, getting up unsteadily to his footing on the eight count.
But the traditional red equipment of the fighter soon pressed ahead again. On the opposite side, the opponent - in opposing blue - was injured early, significant bruising developing under his eye as the fighters exchanged powerful shots.
Rea, twenty-seven, connected with strong blows but the champion, 34, fought fire with fire with stinging uppercuts as the pace seldom decreased over 12 rounds.
The victor barely secured the verdict with official scores of 114-114, 115-113 and 115-112, but the two athletes were persistent and courageous, exactly what their inspiration the legend represented.
